1. The Technical Field
The present invention is directed generally to a solid state keyboard. More particularly, the present invention is directed to a solid state keyboard integrating decorative and functional layers.
2. The Related Art
Keypad input systems typically are assemblies of several components. For example, a typical keypad includes a glass, plastic, or flexible film face plate or front panel that acts as a user interface. This face plate might include graphics that describe the keypad's functionality and/or other indicia, such as a logo, for purely decorative purposes. Such a keypad further includes another panel that includes, for example, field effect sensor electrodes and control circuitry. These two panels typically are manufactured as separate subassemblies that are later joined to form a finished keypad.
Some keypads use reconfigurable keys in connection with a reconfigurable display. One example of such a system includes a dot matrix display that provides prompts to a user and solicits input from the user via one or more mechanical switches, for example, membrane switches, situated about the display and proximate the various prompts. Such a system may guide a user through various menu levels, wherein the displayed prompts corresponding to a particular switch vary from level to level and the function of the switch changes correspondingly. One drawback with such a system is that it is not always clear to the user which switch, if any, is associated with a particular display prompt. Another is that membrane switches, commonly used in such applications, are prone to premature failure when used in high traffic applications.
Computer touch screen technology, as sometimes used in connection with cash register input pads and consumer product information kiosks, offers a better solution, but involves greater cost and complexity. Indeed, such systems typically require PC-based or proprietary decoding hardware. Further, the hardware requirements for such systems prohibit their use in applications where little space is available.